Abstract: A regulated DC and/or AC power supply connected to an AC power source comprising an essentially loss free impedance followed by a controllable device that can sink essentially without losses a selected portion of the current from the essentially loss free impedance. The controllable device can, also essentially without loss, source current from its own internal storage so that the combined residual current can be made available to a load either as a regulated AC quasi square wave or, after rectification, as a regulated DC. A preferred embodiment is described in detail comprising a transformer with a considerable leakage inductance between its primary and secondary. An analog, alternatively a microprocessor-based controller, and a mosfet driver supply a mosfet rectifying bridge with proper gate voltages to obtain a regulated AC and/or DC output. In its simplest form the programmable device may be a generator with controllable phase and amplitude.

Abstract: A device and method for driving a capacitive load that has a more power efficient design. The power efficient capacitive load driving device can be used to drive one or more acoustic transducers of a parametric audio system with low distortion and a flat frequency response. The capacitive load driving device includes a current source, a plurality of switches interconnected in an “H-bridge” configuration coupled to an output of the current source, and a controller. The plurality of interconnected switches is coupleable to at least one capacitive load. By driving the capacitive load with at least one controlled switched drive signal, the capacitive load driving device delivers (recovers) energy to (from) the capacitive load in an optimal manner, thereby generating a desired output voltage waveform across the capacitive load with increased power efficiency.

Abstract: A method for enhancing the detection of prostate specific antigen in a biological sample comprising (a) extracting mRNA from the sample: (b) contacting the mRNA from step (a) with reverse transcriptase under conditions allowing for the production of cDNA; (c) contacting the cDNA from step (b) with a pair of reverse transcriptase polymerase chain reaction primers capable of specifically hybridizing with DNA encoding prostate specific antigen wherein one such primer is an oligonucleotide of 12 to 30 nucleotides in length and comprises the sequence 5-CACCCATCCTA-3' and wherein the second such primer is an oligonucleotide of 12 to 30 nucleotides in length and comprises the sequence 5'-TCCAGCCACGAC-3'; and wherein at least one of the primers is covalently linked to a modified digoxigenin molecule and under conditions allowing for extension of the primers; and (d) detecting the resulting amplified DNA.

Abstract: This invention provides a method of determining the stage of prostate cancer in a human subject using a sample of peripheral blood from a human subject. The invention uses reverse transcriptase-PCR to detect the mRNA encoding prostate specific antigen (PSA) in circulating cells expressing PSA. The invention further uses digoxigenin enhancement of the resultant cDNA signal. The method has an overall sensitivity capable of detecting one PSA expressing cell per 100,000 cells. The method produced no false positives and had a superior detection selectivity for patients with nonlocalized prostate cancer.